1. Field of the Invention
The invention relates to an exercising device, more particularly to a muscle training device.
2. Description of the Related Art
Referring to FIG. 1, a conventional leg exercising device 100 includes a pair of vertically extending slide rails 101 assembled within a generally vertical frame 1, and a stack of weights 102 through which the slide rails 101 are inserted. The vertical frame 1 has top and bottom support bars 2, 3 extending forwardly and respectively from central top and bottom ends thereof. The bottom support bar 3 has a front end connected with a seat frame 4. The top support bar 2 has a front end connected with a front support bar 5 which extends downwardly and inclinedly therefrom and which has a bottom end connected to the seat frame 4. A backrest member 501 and a seat member 401 are respectively connected to a middle section of the front support bar 5 and a top portion of the seat frame 4. The seat frame 4 is provided with a pair of support tubes 402 below the seat member 401. The support tubes 402 of the seat frame 4 are sleeved respectively onto axial rods 403, which in turn are connected respectively with rotary discs 404 at top ends thereof. The rotary discs 404 are fixed respectively with support rods 405, each projecting outwardly from a top face of the respective rotary disc 404. The support rod 405 of each rotary disc 404 is connected with a knee support 406 and an upright pad 407. The axial rods 403 are fixed respectively with sector-shaped cams 408 at bottom ends thereof. The sector-shaped cams 408 are connected respectively with a belt 6 that wraps around the sector-shaped cams 408. The belt 6 is connected to a pulley unit 301 which is connected pivotally to the bottom support bar 3, another pulley unit 103 mounted on the top end of the vertical frame 1, and the stack of weights 102.
To use the conventional leg exercising device 100, a user sits on the seat member 401 with his/her back resting on the backrest 501 and his/her legs straddled over the respective knee supports 406. The legs of the user then push the upright pads 407 toward each other, urging the support rods 405, the rotary discs 404, the axial rods 403, and the sector-shaped cams 408 to rotate synchronously, thereby permitting the belt 6 to lift the stack of weights 102. The combined force applied by the user's legs at this time must be sufficient to lift the stack of weights 102 so as to achieve training of the user's leg muscles.
Although the conventional leg exercising device 100 can achieve its intended purpose, the structure of the conventional leg exercising device 100 is complicated and bulky. Furthermore, since the stack of weights 102 has a substantial weight, when the applied force of the user's legs is released so as to proceed with the next pressing movement, the stack of weights 102 is prone to quickly fall. If this occurs, the upright pads 407 are abruptly moved toward their original positions, which can easily injure the user's legs. Moreover, when the user desires to adjust the load to enhance training of the leg muscles, he/she has to move to the back of the exercising device 100 and manipulate the stack of weights 102 in a known manner. This is a troublesome process.
Referring to FIG. 2, a conventional muscle training device 200 is disclosed in Taiwanese Publication No. 182143. The muscle training device 200 includes two press arms 7 connected pivotally to each other, a torsion spring 8 attached to the junction of the press arms 7 to restore the press arms 7 to their original positions, and a hydraulic cylinder 9 connected between the press arms 7 to control the resistance of the press arms 7. Free ends of the press arms 7 are placed between the user's legs, and are compressed toward each other so as to train the muscles of the user's legs. Since the conventional muscle training device 200 is clamped between the user's legs without any supporting structure, the muscle training device 200 easily falls to the floor during exercise, thereby making it cumbersome and even dangerous to use.